Chair



Dec. 11, 1928. 1,694,617

c. A. BROWN Filed Feb. 2, 1927 2 Sheets-Sheet 1 2 Sheets-Sheet 2 CHAIR na ffin Dec 11, 1928'.

C. A. BROWN Filed Feb. 2, 1927 17727577707: C/uz rjes 1. B r0 w/v 7Patented Dec. 11, 1928.

CHARLES BROWN, OF GARDNER, MASSAOHUfiET'lS, ASSIGEJQR TOE FIELD COMPANY,013 BOSTON, MASSACHUSETTS, A CUBIOBATIQI? SETTS.

iteaerz CHAIR.

Application filed February 2, 1927.

The present invention relates to chairs of the adjustable type, whereinthe seat unit of the chair has a screw threaded connection with the baseor leg structure, to permitraising or lowering of the seat withreference to the supporting floor.

The invention resides in certain improvements in the construction andassemblage of the base or leg portion of such a chair, with particularreference to the retention therein of the internally threaded metal nutmember which receives the screw that is attached to the seat,the generalobject being to mini- 'mize the weight of this base structure, with nosacrifice of its strength and rigidity, all as more fully set forthhereinafter with reference to the accompanying drawings, in which Fig. 1is a. front elevation, showing an ad justable chair in which theimprovements of the present invention are incorporated.

Fig. 2 is an enlarged sectional view of the base or leg structure.

Fig. 3 is an enlarged top plan view of the structure shown in Fig. 2.

Fig. i is an enlarged sectional View on line 41-, Fig. 2, showingdetails of the assemblage of the internally threaded metallic nut memberwith the legs of the base.

Fig. 5 is an enlarged cross sectional view on the line 55 of Fig. 2.

Fig. 6 is a similar view, the sect-ion being taken on the line 6-6 ofFig. 2.

Like reference characters refer to like p arts in the difierent figures.

As shown in the drawings, the base or leg structure of the chair is of ageneral type now in ordinary use, consisting essentially of four bentwood legs 1, 1, which are arranged equidistantly about acentral axis andwhich diverge at their lower ends to form supporting feet 2, 2; in themanner common to bent wood structures of this character, the legs 1, 1are braced by means of a corresponding number of bent wood members 3, 3,the latter preferably being encircled by a bent wood ring 4, adapted toserve as a foot rail for the user of the chair.

In bent wood base structures of this type heretofore used, theinternally threaded nietallic nut member to receive the screw 5,attached to and proj ectingdownwa rdly from the seat unit 6, has beenheld by the upper portions of the legs 1, 1,-said internally thread-Serial No. 185,484.

ed member usually takin the form of a heavy casting provided externallywith ongitudinal undercut grooves into which the cories 20ndinglongitudinal tongues on the inner faces of the legs 1, 1 were forced. incoi suction such as just described, the internally threaded member mustbe extremely heavy; moreover, the forcing of the wooden leg tongues intothe grooves of such a rough casting frequently results in breakage ofthe or of the casting in the assembling process; and the resultingstructure is one that liable to warpage or loosening, due to expansionor contraction of the wood in the absence of similar changes in themetal.

According to the present invention, the usual heavy metallic castingemployed for the internally threaded screw-receiving member is replacedwith a light steel tube '1', the construction of which is best shown inFig. l. Said tube 7, which dispenses entirely with the heretofore-usedleg-receiving external grooves, can be made conveniently on a screwmachine from a. piece of steel of square section, since its essentialfeatures are the usual internal thread 8, (which, being of steel,resists wear by the steel screw 5) and externally, a. pair of squaredcollars 9 and 10, each slight ly removed from the opposite ends of thetube; beyond these collars are the short cylindrical tube sections 11and 12, respectively, and between these collars the tube is preferablyreduced to cylindrical section for the sake of lightness.

From its extreme upper end, adapted to lie flush with the upper surfaceof square collar 9, each bent wood leg 1 presents an internal planesurface 13, which extends downwardly to a point flush with the undersurface of square collar 10,the width of this plane surface 13 beingcoextensive with an edge of the square collars. The lower edge of eachplane surface 13 is defined in each 1 by a. shoulder 14, the latterbeing formed by removing the stock of the leg below said surface, as bymeans of a longitudinal cut or recess 15 in each leg. The four sides oredges of the square collars 9 and 10 thus constitute abutments againstwhich are opposed the four legs 1, 1,the assembly of the latter in arigid structure around the tube 7 being accomplished in the followingmanner A four-armed metallic spider 16, 3, is centrally apertured so asto be received upon Hill the upper tube section 11, and each arm of thisspider overlies the upper end of one of the legs 1, 1,-the material ofsaid spider preferably being flanged downwardly the outer end and on thetwo sides of eacl arm, as shown at 17, to form a soclret that sn glyfits over the upper end of the correspo ding leg 1. A plate 18, Fig. 5,is centrally tured so as to be receive tube section 12, plate thus bear1%, 1e; of the legs 1.

nider 16 and plate 18, for the ion of the leg portions elongated bolts19, 19 are emploved, e preferably havi sl sqnarcd section 21,t apertireof spider 1o to prevent id from turning. hole in each leg ser i saidbolt 19, Whose oiver end, projecting through a correspond'ng hole in theplate 18, is threaded to receive a retaining nut- 22. These nuts 22 areaccessibl for tigl'itening, as by means of a socket \FBllCll, or thwhich is given sufiicient space in which 1. Work by the cuts or recesses15, of legs 1, 1,-it being understood that for this purpose a leg brace23, it used, may be temporarily removed. Each bent Wood leg 1 is firmlyd upon the lower corners of thls and the four ae'ainst the four s Tobind t L ouldcrs the DOLL

esser? sembly, in a manner which eliminates an possibility of relativelongitudinal motion, or lateral or radial play, and it will also be seenthat expansion or contraction of the Wood of the legs, which takes placeacross t is grain and hence at right angles to the bolt 19, can in noway affect the rigidity with which the parts are held together.

1 claim:

In a chair of the class described, a

member having an internally threaded bore, for the. reception of athreaded seat spindle.

id tubular member being formed near ea end with a polygonal. collar, andbeyond eacn collar with a short tubular extension of circular crosssection, chair legs radiating from he axis oi said tubular nien'iber,and each CHAR ns A. BROWN.

